This is the lock of the Inarihan dam located in barangay (village) Binaliw of Calabanga constructed many decades ago.
The THIRIS covers the watershed areas of Tigman, in the towns of Calabanga and Tinambac, Hinagyanan and Inarihan, both in Calabanga, with a total land service area of 3,542 hectares (8,752.47 acres.)
With its towering height of 8,077 feet (2,462 meters), the almost perfect-coned volcano is the main tourist attraction of the province and the regions’ natural wonder.
But don’t be guiled with its beauty and charm, for it has erupted times too many since its first recorded activity in 1776. The most destructive was in 1814 when the town of Cagsawa was buried under its mudflows and only the church belfry was left standing. The town was later relocated into what is now the bustling trade center of Daraga.